Answer:
A presynaptic neuron knows when and how much of a certain neurotransmitter it has to release into the synapse by the frequency of the action potential.
Explanation:
Two nuerons connect to each other through synapse. When an action potential, or nerve impulse, arrives at the axon terminal, it activates voltage-gated calcium channels in the cell membrane, then the calcium which is present in hi highconcentration outside the neuron than inside, rushes into the cell. The Calcium then allows synaptic vesicles to fuse with the axon terminal membrane, releasing neurotransmitter into the synaptic cleft.
The nuerotransmitter than binds to the receptors at the post-synaptic cleft and causes the opening or closing of the channels, hence, depolarizing or hyperpolarizing the cells.This can produce a change in the membrane potential—voltage across the membrane of the receiving cell.
Answer: "homeostatic (dynamic equilibrium) range"
Homeostasis can be observed through the "homeostatic range (pre-set limits)" of the body's pH, temperature and blood glucose.
Explanation:
Homeostasis is the control of internal environment , physical and chemical conditions maintained by the living systems. A body takes control of its internal environment in spite of external forces interruptions. It can be defined as the body's defensive mechanisms.
Homeostasis is maintained and controlled by the nervous system.
Homeostasis is for optimal functioning of the internal environment such as body pH, body temperature, fluid balance, chemical ions balance (calcium, sodium and potassium) and blood glucose.
Body temperature is normally about 37.5° C (98.6° F).
Salt concentration in body fluids is normally about 0.9%
Blood glucose is normally about 10 mg/ml.
A disturbed (imbalanced body as a result of external forces) body regains its haemostasis balance by
Activating reflexes that fight the disturbance and maintaining behaviours to counteract the disturbance.
Answer:
vitamin C and vitamin d
Explanation:
because if the digested first only no vitamin it's supply to our body
examples like eggs